Prostate cancer inducing secondary linitis plastica of the rectum: a rare case report and literature review.

BACKGROUND

Prostate cancer, the most prevalent male malignancy in Western countries, seldom presents as secondary rectal linitis plastica (RLP).

CASE PRESENTATION

We present an 82-year-old man with a 6-month history of altered bowel habits, narrowed stools, and mucous discharge, with absent lower urinary tract symptoms. Serum Prostate Specific Antigen (PSA) was markedly elevated (392 ng/mL). Imaging demonstrated circumferential rectal thickening and a prostatic mass invading the bladder. MRI revealed a "target sign" with associated diffusion restriction. Colonoscopy identified circumferential mucosal protrusions resembling grape-like clusters (Nice Band Imaging (NBI) International Colorectal Endoscopic (NICE) type 3). Deep biopsies confirmed prostatic adenocarcinoma (Gleason score 4 + 3 = 7).

DIAGNOSIS

A multidisciplinary team confirmed the diagnosis of prostate cancer with secondary RLP.

TREATMENT

Combination therapy (prophylactic colostomy, leuprorelin, and abiraterone) reduced PSA from 392 to 2.16 ng/mL within 8 months.

CONCLUSIONS

RLP may mimic various gastrointestinal disorders clinically. Clinicians should consider RLP in elderly men presenting with gastrointestinal symptoms. Definitive diagnosis requires the integration of multi-modality imaging, endoscopy, and histopathological biopsy.